This invention relates to improved building blocks. More particularly it relates to glass building blocks having improved aesthetic and fire resistant properties.
The use of glass blocks in building construction is well-known. They are employed in place of masonry bricks in walls, for example where it is desired to permit viewing through an exterior wall. They are also employed to form internal walls or parts thereof to permit the passage of light and/or for aesthetic reasons.
In GB 1 294 308 there is described a building block comprising a hollow transparent body partially filled with a liquid (e.g. water) and having one oblique wall such that light can be reflected, refracted and filtered by the body of the blocks and by the contained liquid.
In GB 1 495 951 there is described a wall structure comprising a plurality of superposed hollow blocks of material transparent to visible light such as glass. The blocks are partially filled with a transparent liquid (e.g. water) and also contain a prismatic body such that light can be reflected, refracted and filtered. Such a building block is capable of transmitting light through the wall.
It is also known from U.S. Pat. No. 2,724,260 that certain faces of glass blocks may be coated with a thin film of organopolysiloxane to prevent the adhesion of mortar thereto.
Glass building blocks are normally hollow and while, to some extent, they perform a practical and aesthetic function it would be advantageous if either or both of these functions could be enhanced.
We have now found that such an advantage may be realised if there is introduced into a hollow glass block an organosiloxane composition which is thereafter cured to an elastomeric or gel-like state.